Your length is measured spring eye to spring eye like this:
sounds like yours are 48". How wide are your springs?
With these two measurements you should be able to determine weather or not they are stock or not. Furthermore, the measurement will lead you to what springs manufacturer you need, i.e. chevy, ford, etc. From that point you'll just have to determine how much lift you need. Another option would be to just stop by an off road shop & seek their advice. Was it a front or rear spring you broke? Chances are you'll need new springs all around or run the risk of changing a spring after each wheeling trip this summer.